<?php //$Id: date.php,v 1.1.2.2 2007/12/11 13:01:13 nfreear Exp $

require_once($CFG->dirroot.'/user/filters/lib.php');

/**
 * Generic filter based on a date.
 */
class user_filter_date extends user_filter_type {
	/**
	 * the fields available for comparisson
	 */
	var $_field;

	/**
	 * Constructor
	 * @param string $name the name of the filter instance
	 * @param string $label the label of the filter instance
	 * @param boolean $advanced advanced form element flag
	 * @param string $field user table filed name
	 */
	function user_filter_date($name, $label, $advanced, $field) {
		parent::user_filter_type($name, $label, $advanced);
		$this->_field = $field;
	}

	/**
	 * Adds controls specific to this filter in the form.
	 * @param object $mform a MoodleForm object to setup
	 */
	function setupForm(&$mform) {
		$objs = array();

		$objs[] =& $mform->createElement('checkbox', $this->_name.'_sck', null, get_string('isafter', 'filters'));
		$objs[] =& $mform->createElement('date_selector', $this->_name.'_sdt', null);
		$objs[] =& $mform->createElement('checkbox', $this->_name.'_eck', null, get_string('isbefore', 'filters'));
		$objs[] =& $mform->createElement('date_selector', $this->_name.'_edt', null);
		$grp =& $mform->addElement('group', $this->_name.'_grp', $this->_label, $objs, '', false);
		$grp->setHelpButton(array('date',$this->_label,'filters'));

		if ($this->_advanced) {
			$mform->setAdvanced($this->_name.'_grp');
		}

		$mform->disabledIf($this->_name.'_sdt[day]', $this->_name.'_sck', 'notchecked');
		$mform->disabledIf($this->_name.'_sdt[month]', $this->_name.'_sck', 'notchecked');
		$mform->disabledIf($this->_name.'_sdt[year]', $this->_name.'_sck', 'notchecked');
		$mform->disabledIf($this->_name.'_edt[day]', $this->_name.'_eck', 'notchecked');
		$mform->disabledIf($this->_name.'_edt[month]', $this->_name.'_eck', 'notchecked');
		$mform->disabledIf($this->_name.'_edt[year]', $this->_name.'_eck', 'notchecked');
	}

	/**
	 * Retrieves data from the form data
	 * @param object $formdata data submited with the form
	 * @return mixed array filter data or false when filter not set
	 */
	function check_data($formdata) {
		$sck = $this->_name.'_sck';
		$sdt = $this->_name.'_sdt';
		$eck = $this->_name.'_eck';
		$edt = $this->_name.'_edt';

		if (!array_key_exists($sck, $formdata) and !array_key_exists($eck, $formdata)) {
			return false;
		}

		$data = array();
		if (array_key_exists($sck, $formdata)) {
			$data['after'] = $formdata->$sdt;
		} else {
			$data['after'] = 0;
		}
		if (array_key_exists($eck, $formdata)) {
			$data['before'] = $formdata->$edt;
		} else {
			$data['before'] = 0;
		}
		return $data;
	}

	/**
	 * Returns the condition to be used with SQL where
	 * @param array $data filter settings
	 * @return string the filtering condition or null if the filter is disabled
	 */
	function get_sql_filter($data) {
		$after  = $data['after'];
		$before = $data['before'];
		$field  = $this->_field;

		if (empty($after) and empty($before)) {
			return '';
		}

		$res = "$field > 0" ;

		if ($after) {
			$res .= " AND $field >= $after";
		}
		if ($before) {
			$res .= " AND $field <= $before";
		}
		return $res;
	}

	/**
	 * Returns a human friendly description of the filter used as label.
	 * @param array $data filter settings
	 * @return string active filter label
	 */
	function get_label($data) {
		$after  = $data['after'];
		$before = $data['before'];
		$field  = $this->_field;

		$a = new object();
		$a->label  = $this->_label;
		$a->after  = userdate($after);
		$a->before = userdate($before);

		if ($after and $before) {
			return get_string('datelabelisbetween', 'filters', $a);

		} else if ($after) {
			return get_string('datelabelisafter', 'filters', $a);

		} else if ($before) {
			return get_string('datelabelisbefore', 'filters', $a);
		}
		return '';
	}
}
?>